The invention relates to remote authoring of web pages. In particular, the invention is a system and method for what-you-see-is-what-you-get (WYSIWYG) authoring of web pages using ordinary web pages as the interface.
A web site is a source of stored or dynamically generated web pages. Web pages consist of ascii text and are expressed in a formal language known as HyperText Markup Language (html). Web pages are usually sent from one machine (the server) to another (the client). The two machines may be the same, but ordinarily they are separate machines that communicate via a network.
The term xe2x80x9cserverxe2x80x9d can mean both the physical machine that is sending web pages, and the software on the machine that responds to requests for pages. Where it is necessary to distinguish, the term xe2x80x9cweb serverxe2x80x9d is used herein for the former.
The client requests a web page from the server using a Universal Resource Locator (url). A url has three parts: the protocol by which the client wants to talk to the server, the name of the server, and a third part, which is called the xe2x80x9crequestxe2x80x9d, that indicates what the client wants the server to send it.
Here is an example of a url expressed in a form commonly used today: http://www.foo.com/bar.html. In this url, http indicates the protocol the client uses to send the request to the server. www.foo.com is the name of the server to which the request is to be sent. bar.html is the request that is to be sent to the server.
Most servers would interpret xe2x80x9cbar.htmlxe2x80x9d as a request for an html file stored on disk, and would respond by reading the file and sending it to the client. But how to respond to a request is entirely up to the server. A server could equally well choose to interpret xe2x80x9cbar.htmlxe2x80x9d as a request for a web page containing the current time.
A web page usually contains some amount of text plus html operators specifying how to display the page on the screen. The client software (e.g. a browser) has considerable leeway in deciding how to display the page to the user. The aspect of the display of web pages relevant to the invention is the display of links and forms.
A link is usually a combination of text and/or an image, plus a url. Typical client software will display the text or image with an underline or outline, or some other indication that the text is active. The user can indicate that he wants to follow that link, usually by clicking on it with a mouse. Herein the phrase xe2x80x9cto click on a linkxe2x80x9d refers to a general term to mean whatever method the user uses to indicate that he wants to follow a link.
When the user clicks on a link, the request in the associated url is sent to the web server mentioned in that url. Usually the request will cause the server to send the client another web page, which will in turn contain other links, resulting in an ongoing series of requests from the client interleaved with web pages sent in reply by the server(s).
A form is like a link in that it includes places (i.e. xe2x80x9cbuttonsxe2x80x9d) where the user can click to send a request to a server, but it can also include xe2x80x9cfieldsxe2x80x9d, through which the user can send additional information along with the request. For example, a form field might be a menu of choices, a box in which the user can type text, or a button that the user can toggle on or off.
Herein the phrase xe2x80x9cclient software capable of browsing a conventional web sitexe2x80x9d means software able to: (1) display web pages in some form to the user; (2) display links so that the user can click on them to send the corresponding request to the server named in the url; (3) display forms so that the user can enter information into each field, and click on some button to send the corresponding request, plus the information entered by the user, to the server named in the url; and (4) carry on an ongoing dialogue with a server, where requests from the client alternate with web pages from the server.
Herein the term xe2x80x9clinkxe2x80x9d includes both links and forms, along with any other element of a web page that has an associated url, and which a user can click on to send the request in the url to the server mentioned there.
Two elements are required to publish web pages on the Internet or on an intranet: (1) an authoring tool: software for creating and maintaining the web pages; and (2) a server: a computer that can send (or xe2x80x9cservexe2x80x9d) the web pages to clients who request them. To avoid the expense and difficulty of maintaining their own web servers, users often share servers maintained by someone else. On the Internet, a company that maintains a web server shared by multiple users is called a hosting service. Within a corporate network, a server maintained by the MIS department might play the role of a hosting service for users within the company.
A shared server is not usually at the same location as the user. There are two general ways for a user to create and maintain a web site on such a remote server: (1) the user can use an authoring tool that runs on his own local machine, and then transmit the finished site (or perhaps just changes) to the server; or (2) the user can use an authoring tool that runs on the remote server, sending commands to it over the network. Herein the term xe2x80x9cremote authoringxe2x80x9d refers to the second case. In remote authoring, the user""s local machine is nothing more than an interface. Commands are sent over the network, and executed on the remote server.
The advantages of remote authoring derive from the fact that very little happens on the local machine. For example, no software has to be installed on the local machine if it can already browse web pages. This is an attraction in itself to end users, and it also means that the user is not tied to using any particular computer. Any computer with a browser and a network connection to the server will do. This might include a computer so simple that it is not possible for the user to install software on it: for example, a web-enabled television set.
There are also advantages in reliability. The data for the site is stored on the server, rather than the user""s machine. Servers are generally more reliable than clients, because servers are shared, and there is more at stake if they fail.
Remote authoring of web pages requires two major pieces of software: (1) some kind of database in which the information to be presented in the web site is stored; and (2) a program that generates web pages from information contained in the database. Known remote authoring tools require the user to use these two programs separately. The user would add or change information via the database program, then in a second step, visit and inspect the modified site. The disadvantage of this approach is that the user cannot see the site as he is modifying it.
The configuration of the software on a typical web server is as follows. Client requests are handled by the server, and can be of two types: (1) a request for a particular html file, in which case it reads the file off the disk and sends it to the client; or (2) a request to run a program that yields a web page as a result (a cgi script), in which case it invokes the program and returns whatever web page it generates. The second case is the one that is relevant to remote authoring. In this configuration, the server does little more than relay requests to a collection of predefined programs.
Known remote authoring tools are implemented in terms of scripts. With reference to FIG. 1, the following is an example of how a programmer might build a remote interface to a database, using a cycle of three cgi scripts, called Sselect, Sdisplay, and Supdate.
In step 10, the user initiates the cycle by sending a request to the server to run Sselect. The server calls Sselect. In step 12, Sselect generates an html form that lets the user select a database entry to edit (e.g. a menu of the possible choices), with an xe2x80x9cEditxe2x80x9d button whose url contains a request for Sdisplay. In step 14, the server sends this page to the client, where it is displayed to the user. In step 16, when the user clicks on xe2x80x9cEditxe2x80x9d, the server receives the request from the button that the user clicked on (Sdisplay) along with the name of the entry the user selected. The server then passes that name to Sdisplay. In step 18, Sdisplay reads the entry selected by the user from the database, and generates an html form with fields representing the current value of each part of the entry, plus an xe2x80x9cUpdatexe2x80x9d button whose url has Supdate as its request. In step 20, the server sends this page to the client, where it is displayed to the user. In step 22, when the user clicks on xe2x80x9cUpdatexe2x80x9d, the server receives a request for Supdate, along with possibly modified values for each field in the entry the user selected. The server passes this information on to Supdate. In step 24, Supdate writes the new information to the corresponding entry in the database, then calls Sselect, and the process returns to step 10.
The foregoing represents the state of the art for known remote web site authoring tools. After modifying the contents of the database, the user can view the updated site. But the interface, while editing the site, is that of a database program.
Generally, the invention features a system and method for creating web pages in which ordinary web pages are the interface to the user, and more particularly, web pages representing the site being created by the user. The invention combines the two elements of remote authoring: i.e. editing the site and viewing the site. The interface that the user sees while editing the site is a version of the site itself, reflecting all changes to date.
While the general concept of an authoring tool running on a remote server is known, the invention enables the user to do remote authoring via a xe2x80x9cwhat-you-see-is-what-you-getxe2x80x9d (WYSIWYG) interface. Known remote authoring tools provide the user with a database interface while editing a web site. In contrast, the invention allows the user to see the site as he is editing it.
WYSIWYG software for desktop computers has existed for many years. However, developing WYSIWYG remote authoring software for web pages poses difficulties that do not arise for software that can communicate directly with the operating system of the user""s machine: (1) the interface that the authoring software can display to the user is limited to what you can express using web pages, and (2) the commands sent by the user to the authoring software are limited by the requests that can be sent from a web page to the server. The invention provides a way to do WYSIWYG authoring in spite of these difficulties.
The invention features a system (and method) for remote authoring where web pages representing the site being created are generated dynamically by the server. Each link generated by the server contains a unique key, and at the time the server generates the link, it also generates a program that is to be executed if the user clicks on that link. The program is stored in a table within the server, indexed under the corresponding key. When the user clicks on a link, the key is extracted from the request sent to the server, which retrieves and executes the program stored in its table under that key.
When executed, the program will usually generate and send to the user a new web page, and generate and store within the server new programs for each link on the page. So the code executed by the server as it responds to several successive clicks will consist of a sequence of programs, each generated by the preceding one.